Head gasket installation

tubman said:
I see the problem here. Both you and "Ronnie Roadster" are serious racers. You exist in a whole different world than most of us on here. Look at it this way : The engines in top fuel dragsters are basically completely rebuilt between every round; does this mean that those of us with regular "street" engines should do the same? I think not.

Also, composite big bore gaskets are readily available. My latest build has a 3 5/16" bore and I had no problem finding gaskets. It also has a MAX-1, Edmunds heads and upgraded ignition and carburation systems. I don't consider it a stock engine.

I try to buy all of the reasonably priced flathead finned aluminum heads I can. I pass on the majority of heads I find because of excessive corrosion.
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I could be wrong, but by big bore, I think we are talking about 3 3/8" and above.

My current build is 3 3/8" +.030 and I didn't find composite that large nor was it recommended.

To each is own, but I think 3 5/16", albeit a nice large bore, still falls within the stock sized head gasket.

Please someone correct me if this is wrong information.
 
Nope. Big bore composite gaskets from Speedway (I believe they were Fel-Pro). BTW, I had considered running standard gaskets until I fitted one on my engine and saw how it overlapped the bore slightly. I didn't want to take a chance of the steel "fire ring" on a standard gasket protruding into the combustion chamber, even if by a little bit.

It's odd.There are a lot of folks on here that will tell you that you shouldn't go over .060 overbore on any flathead, and also some that are talking bores larger than 3 3/8". I have never been lucky at anything, so I'll stick to 3 5/16" myself. I wonder how many people realize that you can make a 258" flathead (3 5/16" bore and standard stroke), a lot cheaper than you can make a 255" flathead by going the Merc crank route? (Plus it will have reduced piston speed.)
 
tubman said:
Nope. Big bore composite gaskets from Speedway (I believe they were Fel-Pro). BTW, I had considered running standard gaskets until I fitted one on my engine and saw how it overlapped the bore slightly. I didn't want to take a chance of the steel "fire ring" on a standard gasket protruding into the combustion chamber, even if by a little bit.

It's odd.There are a lot of folks on here that will tell you that you shouldn't go over .060 overbore on any flathead, and also some that are talking bores larger than 3 3/8". I have never been lucky at anything, so I'll stick to 3 5/16" myself. I wonder how many people realize that you can make a 258" flathead (3 5/16" bore and standard stroke), a lot cheaper than you can make a 255" flathead by going the Merc crank route? (Plus it will have reduced piston speed.)
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Tubman,

My journey with a block was not a good one and is the same experience many others has had.

To start, I thought I had a 59AB that an incompetent machine shop did all the work on 3 5/16" bore, etc. They did not mag the valve valley. Upon pressure testing, a 8" crack showed up at 20 lbs. My builder likes to go to 50, so that block is slide lined for a later date. That part of the block is very thin. It may need to be epoxied and not TIG'd.

Two 99A Merc blocks, both cracked into bore through intake seat. Will eventually get them fixed, but not at this time.

8RT block I have is good, but has some brazed repair on the valve seats. This block is now destined for an Ardun set up.

Last chance block was a 59L motor that my buddy gave me. It was already out to 3 3/8ths when I got it. We were hoping to just clean it up @ +.010". No dice.

Thorough sonic testing revealed the walls were still plenty thick so it finally cleaned up at +.030". The finished bore size was 3.4050"

With a 4" stroke, it makes this motor a 292".

After tearing down 5 blocks in a short period of time, I am convinced that its not just bore size that makes these motors overheat, but the **** that gets caked in the water jackets.

All five blocks had crud that went about 1/2 up the outside portion of the cylinder wall. Top that with an out of tune or poorly timed motors, clogged radiators, inefficient water pumps, etc, I can see why they overheated.

The 59L block had some much crud inside, I could drive a long screw driver into it like a stake. I'm not kidding. It was the worst I've ever seen.

My block for the 292 has had every last bit of rust, scale, and sand cleaned out it.

The coolant will have complete water to metal contact. I'm using a Walker radiator, correctly timed ignition, metric ring pack and Skip's pumps, I'm confident there will not be any problems cooling this motor.
 
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Tim, I agree with everything you are saying. It's just, that with my luck, I'd be taking all 5 blocks to the scrapper. I think I have mentioned here that I sold my second to the last good 8BA block to a local guy who had been through 5 engines with blocks that were essentially junk. I don't see why anyone would be putting thousands of dollars of labor and parts into a block that was not squeaky clean. I think back in the day, nobody even considered this; a quick dip in the hot tank and then off to the machining. Even the last 258" engine I just finished, the bores looked good and it sonic tested to go to 3 3/8". After the bore to 3 5/16, a casting flaw showed up (a big pit). My machinist said I could probably run it as is, but we decided to sleeve that cylinder just to be sure.

Now, let's get back to the O/P's question. Over the years I have built 4 flatheads from the ground up. I know that's nothing compared to some people on here, but I never had the need to deck any of the blocks, and never had any problems with the heads not sealing without using sealer. That was with three sets of finned aluminum heads and one set of stockers.
 
tubman said:
I see the problem here. Both you and "Ronnie Roadster" are serious racers. You exist in a whole different world than most of us on here. Look at it this way : The engines in top fuel dragsters are basically completely rebuilt between every round; does this mean that those of us with regular "street" engines should do the same? I think not.

Also, composite big bore gaskets are readily available. My latest build has a 3 5/16" bore and I had no problem finding gaskets. It also has a MAX-1, Edmunds heads and upgraded ignition and carburation systems. I don't consider it a stock engine.

I try to buy all of the reasonably priced flathead finned aluminum heads I can. I pass on the majority of heads I find because of excessive corrosion.
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Theres really no problem here you see I drive on a daily basis modified flatheads and my ARDUN all with aluminum heads and copper head gaskets going over 1000,000 miles and counting. Heck this year I will have owned my Deuce roadster for 46 years now and guess what during all that time NEVER have I had any issues with corrosion due to electrolysis. So to each there own both will work perfectly fine so when you say never you really should think about what your trying to guide people on.
Ronnieroadster
 
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^ probably the non use of suitable corrosion inhibitors (now just commonly called anti-freeze or summer coolant).

Sorry this was in response to 51 Merc CT's question.
 
Probably a non issue now days. maybe never... guess enough that we post about it. Not sure we do the same about waterpump gaskets. But maybe we do.


I like composites even for iron heads. I'd guess the copper ones are very decent for you high compression guys.
 
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Edelbrock makes aluminum heads and has both copper and composite gaskets for their heads. I ordered the composite, and the water jacket holes are edged with a copper ringed edge. I asked their tech about a sealant, and they said either nothing or permitex spray copper gasket.
 
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